RESTful JSON web databases

JSON Web Databases

Applied JSON: HTTP REST, Ajax databases and beyondKris Zyp

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HTTP/REST + JSON =Database interaction for

the web


Overview

Interoperability BasicsTools/FrameworksBeyond simple CRUD


Interoperability Basics

• HTTP RESTGET - query and get by id

PUT - update an object

POST - create an object

DELETE - delete an object


Tools/Frameworks

Client SidePersevereJesterDojo

Server SideActiveResourceCouchDBPersevereGrassyKnoll...


Standard Conventions

Objects/records accessible by /table/id/Product/12GET, PUT, and DELETE this resource

Sub object URLs determined by object identity properties

GET /Product/[{“id”:”11”, “name”:”Dérailleur”}, {“id”:”12”, “name”:”Handle Bar”}]


The post-ORM realm


Schemas

• DB defined schema - ActiveRecord

• Schema free - CouchDB


Evolutionary Schema:Persevere


JSON Schema based evolutionary schema

Start without a schema

Add constraints

as application

evolves


schema:

{"description":"A person",

"type":"object",

"properties":

{"name": {"type":"string"},

"age" : {"type":"integer",

"maximum":125}}

}

instance:

{“name”:”Kris”,

“age”:30}

schema:

{"description":"A person",

"type":"object",

"properties":

{"name": {"type":"string"},

"age" : {"type":"integer",

"maximum":125}}

}

instance:

{“name”:”Kris”,

“age”:30}

JSON Schema


JSON Schema driven UIStart with schema

and simple form


http://goessner.net/articles/JsonPath/

Querying

Web-safe portability importantSQL extremely hard to make secure and too complicated in the browserJSONPath

JavaScript-style syntaxLanguage agnosticEasy to secure


http://goessner.net/articles/JsonPath/

XPath like query language for JSON

Filters - [?expr]

Properties/paths (like JS) - .prop

Recursive descent - ..prop

Slice operator – [3:10:2]

Union operator - [3,4,5]

XPath like query language for JSON

Filters - [?expr]

Properties/paths (like JS) - .prop

Recursive descent - ..prop

Slice operator – [3:10:2]

Union operator - [3,4,5]

JSONPath


REST URLs + JSONPath = Web querying

/Table/ - All the objects in a table

/Table/[[email protected] < 10] – all items with a price under $10

/Table/..name – A list of the name property values

/Table/.length – A count of the items in the table

REST URLs + JSONPath = Web querying

/Table/ - All the objects in a table

/Table/[[email protected] < 10] – all items with a price under $10

/Table/..name – A list of the name property values

/Table/.length – A count of the items in the table

JSONPath querying in requests


http://www.sitepen.com/blog/2008/07/16/jsonquery-data-querying-beyond-jsonpath/

Lenient Syntax - ?price<10

Sorting - [/price, \rating]

Mapping - [=firstName+' '+lastName]

Wildcarding [?description='*fun*']

Recursive object filter - ..[?name='Bar']

Example URL: /Table/[?price<10] [={name:name, rating: rating}] [\rating]

Lenient Syntax - ?price<10

Sorting - [/price, \rating]

Mapping - [=firstName+' '+lastName]

Wildcarding [?description='*fun*']

Recursive object filter - ..[?name='Bar']

Example URL: /Table/[?price<10] [={name:name, rating: rating}] [\rating]

JSONQuery


http://www.sitepen.com/blog/2008/06/17/json-referencing-in-dojo/

JSON Referencing

Hyperlinking + JSON

• Cyclic

• Multiple references

• Cross-message references

• Cross-site references



{“name”:”Kris Zyp”,“id”:”kriszyp”,“children”:[{“id”:”jennikazyp”,“name”:”Jennika Zyp”}],“spouse”:{“name”:”Nicole Zyp”,“spouse”:{“$ref”:”kriszyp”},“children”:[{“$ref”:”jennikazyp”}]

}}

{“name”:”Kris Zyp”,“id”:”kriszyp”,“children”:[{“id”:”jennikazyp”,“name”:”Jennika Zyp”}],“spouse”:{“name”:”Nicole Zyp”,“spouse”:{“$ref”:”kriszyp”},“children”:[{“$ref”:”jennikazyp”}]

}}

JSON Referencing



{“name”:”Kris Zyp”,“children”:[{“name”:”Jennika Zyp”}],“spouse”:{“name”:”Nicole Zyp”,“spouse”:{“$ref”:”#”},“children”:{“$ref”:”#.children”}

}}

{“name”:”Kris Zyp”,“children”:[{“name”:”Jennika Zyp”}],“spouse”:{“name”:”Nicole Zyp”,“spouse”:{“$ref”:”#”},“children”:{“$ref”:”#.children”}

}}

JSON Referencing



{“name”:”Kris Zyp”,“id”:”kriszyp”,“children”:[{“name”:”Jennika Zyp”}],“friends”:[{“$ref”:”jesse#.spouse”}]

}

{“name”:”Kris Zyp”,“id”:”kriszyp”,“children”:[{“name”:”Jennika Zyp”}],“friends”:[{“$ref”:”jesse#.spouse”}]

}

JSON Referencing


http://sitepen.com/labs/persevere.php

"schema":{

“name”:”Friend”,

“properties”:{

“firstName”:{“type”:”string”},“age”:{“type”:”integer”},

}

"staticCreateMethod":function(arg1){

var friend = new Friend;

friend.age = 0;

},

"prototype":{

“myMethod”:function(){

return this.firstName + ‘ ‘ + this.lastName;

}

}

"extends":{"$ref":"../Person"}

}

"schema":{

“name”:”Friend”,

“properties”:{

“firstName”:{“type”:”string”},“age”:{“type”:”integer”},

}

"staticCreateMethod":function(arg1){

var friend = new Friend;

friend.age = 0;

},

"prototype":{

“myMethod”:function(){

return this.firstName + ‘ ‘ + this.lastName;

}

}

"extends":{"$ref":"../Person"}

}

Server side JavaScript + web storage


Security with web accessible data storageTypical databases behind the applicationWeb DBs are directly accessible

User authorization becomes integrated with dataAllows separation of application and security concerns


Security with Persevere

Data-centricCapability-basedLogic/code based security possible as well


Transactions


Live Data Notifications with REST Channels

http://cometdaily.com/2008/05/13/http-channels-2/


Other Features

File storage/alternate resource representationsUtilize existing SQL tablesSMD supportClass/Table Inheritance


Persevere

JSONQuery/JSONPathJSON ReferencingComet Live Data NotificationsJSON Schema with evolutionary constraintsJSON-RPCBuilt-in SecurityStandards based REST interface

http://sitepen.com/labs/persevere.php


REST/ Ajax databasesDevelop for the future


Technology

RESTful JSON web databases